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101.
Morrison Adrian R.; Sanford Larry D.; Ball William A.; Mann Graziella L.; Ross Richard J. 《Canadian Metallurgical Quarterly》1995,109(5):972
Alert wakefulness (W) and rapid eye movement sleep (REM) are remarkably similar on several measures of brain activity, but 2 differences in REM are reduced sensory responsiveness and atonia in postural muscles. Pontine tegmental lesions create REM without atonia (REM-A), releasing motor behavior. In 9 cats, we studied the acoustic startle reflex (ASR), orienting (OR), and ponto-geniculo-occipital waves (PGOE) elicited by tones during W, REM, REM-A, and non-REM (NREM). OR occurred in W and REM-A, being most complete in cats with the most elaborate spontaneous behavior. ASR occurred in W, NREM, and REM-A in lesioned cats. In normal cats, ASR rarely appeared in NREM and REM. PGOE had similar characteristics in both groups. The similarity of REM to W is particularly obvious when cats lack motoneuronal inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
We calculate to first order the static stress distribution around cracks which are slightly perturbed from semi infinite straight planar geometry and are subject to type I loading. We find that both in-plane and out-of-plane perturbations give rise to local stress distributions which tend to suppress the deviations in the posterior (quasistatic) propagation of the crack. 相似文献
103.
Although self-report data are generally evaluated as reliable, validity estimates for self-reported drinking behavior are not as favorable. A new method of measurement addressing problems currently associated with the questionable validity of self-report drinking information is introduced. Study 1 tests the correspondence between the new measure (occasions per year blood alcohol level exceeded 0.08%), traditional self-report measures, and laboratory alcohol consumption. The novel measure correlated most strongly with volume of alcohol consumed in the laboratory compared to the traditional measures. In Study 2 the novel measure was favored over a traditional measure when discriminating between the presence and absence of problem-drinking symptoms. 相似文献
104.
105.
For nonlinear systems it is not a mathematically obvious fact that the simplest feedback system yields equations which are solvable, even when the gain in the loop is ⩽1. The authors treat this and more general issues. For example, it is not known (for a continuous-time system) if unity feedback for a plant C with gain <1 produces a well-posed system. It is shown that if the gain of C is <1 and C also loses sufficient efficiency at high frequency, then indeed the feedback system is well posed. The hypothesis that the gain of C is <1 can be replaced by the reasonable assumption that C saturates on large enough signals, and well posedness is still obtained. This approach also applies directly to electrical circuit connections. It is proved that rather general connections of amplifiers are well posed under the assumption that the amplifiers saturate and that they lose efficiency at high frequency 相似文献
106.
RO Obaro 《Canadian Metallurgical Quarterly》1995,68(816):1369-1370
107.
The validity of an alternative 5-factor measure of personality, the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ), was assessed in 450 cocaine abusers seeking outpatient treatment. As predicted, the ZKPQ Impulsive Sensation Seeking (ImpSS), Neuroticism-Anxiety (N-Anx), and Aggression-Hostility (Agg-Hos) scales were associated with greater drug abuse and psychiatric severity and symptoms and worse outcome (p? 相似文献
108.
Ball Samuel A.; Rounsaville Bruce J.; Tennen Howard; Kranzler Henry R. 《Canadian Metallurgical Quarterly》2001,110(2):341
The authors compared the internal consistency, 1-year temporal stability and self-informant agreement of ratings of personality trait (NEO Five-Factor Inventory; NEO-FFI; P. T. Costa & R. R. McCrae, 1992) and personality disorder symptom severity (Structured Clinical Interview for DSM-III-R personality Disorders Questionnaire; SCID-II-Q ; R. L. Spitzer, J. B. W. Williams, M. Gibbon, & M. First, 1990) in 131 substance-dependent inpatients. Internal consistency coefficients were acceptable to very good for most NEO-FFI and SCID-II-Q scales, and temporal stability correlations were significant for all measures. Agreement between patient and informant ratings was more modest. Substance abuse and depression symptom severity moderated the temporal stability and self-informant agreement of several personality trait and disorder ratings. The authors did not find that the five factors were more reliable than the Axis II symptoms. Issues related to the reliability of personality assessment in multiply diagnosed patients are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
In this paper, we propose a double aperture double-gate AlGaN/GaN vertical high-electron-mobility transistor (HEMT) to improve the device characteristics, such as the current and the ON resistance (\(\hbox {\textit{R}}_{\mathrm{ON}}\)). The proposed vertical HEMT results are compared to the conventional single aperture single-gate vertical HEMT of equal dimensions, and increased drain current and lower \(\hbox {\textit{R}}_{\mathrm{ON}}\) are shown. A comprehensive simulation study has also been carried out for the proposed device, to analyse the impact of thickness and doping concentration of aperture, drift region, and current blocking layer. In addition, the effect of different materials in current blocking layer on device characteristics is also studied. The obtained results and their effect on device characteristics have been thoroughly analysed and explained accordingly. 相似文献
110.
This paper presents the use of the induction motor current to identify and quantify common faults within a two-stage reciprocating compressor based on bispectrum analysis. The theoretical basis is developed to understand the nonlinear characteristics of current signals when the motor undertakes a varying load under different faulty conditions. Although conventional bispectrum representation of current signal allows the inclusion of phase information and the elimination of Gaussian noise, it produces unstable results due to random phase variation of the sideband components in the current signal. A modified bispectrum based on the amplitude modulation feature of the current signal is then adopted to combine both lower sidebands and higher sidebands simultaneously and hence characterise the current signal more accurately. Based on this new bispectrum analysis a more effective diagnostic feature, namely normalised bispectral peak, is developed for fault classification. In association with the kurtosis value of the raw current signal, the bispectrum feature gives rise to reliable fault classification results. In particular, the low feature values can differentiate the belt looseness from the other fault cases and different degrees of discharge valve leakage and inter-cooler leakage can be separated easily using two linear classifiers. This work provides a novel approach to the analysis of stator current for the diagnosis of motor drive faults from downstream driving equipment. 相似文献